Electromechanical Time Lapse Trigger

Introduction: Electromechanical Time Lapse Trigger

Despite my poor email etiquette, Trebuchet and I had talked about posting these concurrently. Since he , rightfully, went ahead when he didn't hear from me, I'm dashing mine out really quickly.

I should note that two of these videos are of Magnesium sulfate coming out of solution. And the video in Salt Crystal garden was made with this rig.

Step 1: What I'm Using

a pair of old servos
wire
pair of old batteries
and other junk
gearhead motor (optional)

Step 2: Disassemble the Servos

I disassembled to old tower hobbies servos that dies after spending a week on the bottom of the Econ River. Nice thing about these servos is that they use the same pitch gear through out making interfacing easy.

Once you disassemble the servos remove any stops that prevent full rotation and one gear is mounted on a pot, instead of fashioning a new axle I just removed the guts from the pot to let it spin freely.

Step 3: Make a Mount

I contrived a holder out of scraps of plywood, and after discovering the two servos would link together, made a few careful measurements and mounted them. With this I discovered i could attain a rotation speed between 1 per 2 sec and 1 per 40 sec. I wanted the ability to go slower still, so i found a gearhead motor in my junk box along with the right sized gear and now can go as slow as 1 per 5 minutes.

Step 4: Actuator

The actuator took a bit of thought i wanted something that wouldn't mash my camera to death, i decided on a cam made from a film canister lid hot glued to the servo arm.

Additionally the camera did not accept a power adapter and a pair of batteries was modified to feed power from a wall wart to the camera, the tape prevents the batteries constantly charging.

Step 5: That's It

A mount was made from spring clamp, scrap wood and an old aluminum ruler, set it so the cam activates the shutter and walk away for a few hours. speed is varied by voltage.

Comments

Very nice! I'd actually love to build a hybrid of the two - I've got a setup for programming AVRs, so I can implement remote control, time-lapse, programmable, what have you, but I don't want to open my digital camera - I've seen how they're put together and I'm afraid of butchering my favourite camera!
So I would like, ideally, to construct something along the lines of this project to physically push the button, but have it driven by the AVR. My problem is, where do I get actuators? I had in mind some sort of solenoid to push the button, but your cam arrangement seems much gentler on the camera, and little motors should be more available. Or perhaps a rack-and-pinion arrangement... too bad LEGO(tm) is so expensive.
So thanks!

I need to do something similar to this (and you), except for a DV camera. The problem with solenoids is that they are not very elegant. When activated they "punch" whatever they're pointing at. You have to worry about finding the right solenoid both in terms of force as well as throw (the distance over which they travel). I'm convinced that the way to go is with a servo, and just let one of the arms depress the button at whatever interval you want your uC to do its thang. Seems as though it would take a small amount of trial and error to figure out how much of an angle you need to spin the servo depending on where/how it's mounted relative to the camera, but that seems like small effort compared to getting the solenoid right.
If you were lucky with your camera's button layout, you might even be able to rig-up a single servo to twist one way to turn on the camera, the other way to press the shutter button, then back again to turn it off.
Thanks for the ideas, TUA.